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  4. How gravity works in spiral galaxy?
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How gravity works in spiral galaxy?

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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #520 on: 19/08/2019 13:52:08 »
Some more information about magnetic fields:

You can calculate the force that a magnetic field has on a charged particle using the following equation:

F = qvBsinθ, where

“F” is the resulting force in newtons
“q” is the charge in coulombs
“v” is the velocity in meters per second
“B” is the magnetic field strength in teslas (1 tesla = 10,000 gauss)
“sinθ” is the angle between the direction of the particle’s motion and the direction of the magnetic field lines

When we consider moving a proton across a magnetic field at an angle of 90 degrees to the field line orientation (in order to maximize the force), two things stand out. (1) A strong magnetic field can apply a large force to a slow-moving proton (doubling the field strength doubles the force), but just as importantly (2) A weak magnetic field can apply a large force to a fast-moving proton (doubling the speed doubles the force). So you don’t need an especially powerful field if the proton is already moving very quickly. The particles in an accretion disk near the event horizon are indeed moving very quickly because the disk is very hot.

For hydrogen plasma at a temperature of 1 million degrees Celsius, the average speed of the protons is about 146,000 m/s. For 10 million degrees, it’s around 460,000 m/s. 100 million is 1,455,000 m/s and 1 billion is 4,600,000 m/s. These numbers were calculated with this: https://www.omnicalculator.com/physics/particles-velocity#average-velocity-of-gas-particles

Just as a caution for the above calculator, it assumes classical physics. That is, the resulting numbers will become inaccurate when the particle velocity approaches a significant fraction of the speed of light. So the velocity it outputs for temperatures of many billions or trillions of degrees may be inaccurate (the resulting velocity will be an over-estimate).

So for a field strength of 1 tesla (10,000 gauss), the resulting force on a proton moving at 146,000 m/s is:

F = qvBsinθ
F = (+1.6021766208 x 10-19 C)(146,000 m/s)(1 T)(sin90o)
F = (2.3391779 x 10-14)((sin90o)
F = 2.0912172 x 10-14 newtons

This amounts to an acceleration of about 1.25 x 1013 meters per second squared (or about 1.276 trillion times the acceleration due to Earth’s surface gravity). Since the force increases linearly with particle velocity, the force at 10 million degrees is about 4 trillion times Earth’s gravity, 100 million degrees is 12.7 trillion times Earth’s gravity and 1 billion degrees is 40 trillion.

So super-strong fields aren’t strictly necessary for very high particle accelerations.
« Last Edit: 19/08/2019 13:55:42 by Kryptid »
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #521 on: 19/08/2019 14:38:57 »
Quote from: Kryptid on 18/08/2019 18:42:07
This article estimates field strengths of up to 10,000 Gauss for NGC 4258 right at the event horizon: https://arxiv.org/pdf/0909.1207.pdf
Wow
That's really good news.
Quote from: Kryptid on 18/08/2019 18:42:07
Closer in, the magnetic field could be much stronger (the measurement was made in a part of the disk about 7.5 million kilometers from the center of the disk)
So, as we move closer to the center of the SMBH, the magnetic field is stronger.
Therefore, if new pair of particles had been created at the event of horizon or very close it:
https://en.wikipedia.org/wiki/Pair_production
"Pair production is the creation of a subatomic particle and its antiparticle from a neutral boson."
"if one particle has electric charge of +1 the other must have electric charge of −1, or if one particle has strangeness of +1 then another one must have strangeness of −1"
Do you agree that at the moment of creation, one particle has electric charge of +1 while the other must have electric charge of −1 and they are probably moving very close to each other at high orbital velocity.
Do you agree that Lorentz force due to that magnetic power of 10,000 Gauss could affect their movement directions?
If one will be pushed inwards to the center of the SMBH, the other one will be pulled outwards from the event horizon (directly into the accretion disc) at the same moment of creation due to Lorentz force under opposite electric charges.
Why not?
If you agree with that, than the accretion disc gets its matter from the event of horizon (or deeper) without any violation of any law of physics.
Quote from: Kryptid on 18/08/2019 18:42:07
By the way, where did you get that number of 0.8c for the relativistic jet from a super-massive black hole?
Halc have asked the same question and even had set the calculation:
Quote from: Halc on 22/07/2019 22:20:23
There is a 10k sun-mass amount of material moving at 0.8c?  How does it not exit the galaxy?  That's well above escape velocity from 'high above the disc plane'.
Quote from: Dave Lev on 26/07/2019 18:57:34
Ghostly Gamma-ray Beams Blast from Milky Way's Center
https://www.cfa.harvard.edu/news/2012-16
The two beams, or jets, were revealed by NASA's Fermi space telescope. They extend from the galactic center to a distance of 27,000 light-years above and below the galactic plane.
The jets were produced when plasma squirted out from the galactic center, following a corkscrew-like magnetic field that kept it tightly focused.
It would take a tremendous influx of matter for the galactic core to fire up again. Finkbeiner estimates that a molecular cloud weighing about 10,000 times as much as the Sun would be required.
Quote from: Halc on 26/07/2019 19:55:03
OK, that mentions a 10k solar mass cloud being required to get back into 'gulp' mode from its current 'sip' mode.  No mention of anything moving at 0.8c mentioned.  The detected bubble is faint (not massive), and is an effect from a 'gulp' perhaps a million years ago.  The bubble extends to 27000 LY, so it's moving at best at 27 ly per 1000 years, hardly 0.8c.
The jets, if fast moving material, are the produce of the current 'sip' mode.  If they're a remnant of the big mass from a million years ago, the jets must be slow indeed to still be there.
That brings me to the following critical issue with regards to The Virial Theorem and Dark Matter:
Our scientists claim that our Sun orbits around the center of the galaxy due to the impact of The Virial Theorem and Dark Matter.
It is also stated:
https://web.stanford.edu/~ajlucas/The%20Virial%20Theorem%20and%20Dark%20Matter.pdf
"Modern estimates put the percentage of the universe made up of dark matter at about 80-90%. We still
have very little idea as to what makes up dark matter."
Based on the Virial Theorem, do you agree that same total mass that holds by gravity any star (including the Sun) in the spiral disc must also apply to that molecular Jet stream (for the same radius)?
If so, how could it be that in the spiral arms we see clearly that the all stars obey to that Virial Theorem and orbit around the center, while the molecular jet stream ignore it completely?
It might contradicts the basic idea of  Virial Theorem and Dark Matter, unless we set the followig calculation:
Quote from: Kryptid on 18/08/2019 18:42:07
Have you actually done some math that shows that measurement to be wrong?
OK.
The orbital velocity for any star in the spiral disc is:
V^2 = G M /r
M total (due to viral + Dark matter) = V^2 r /G
As most of the stars in the spiral disc orbits at 220 K/s
Than the total center mass that with regards to the radius is:
M total = 220 K/s ^2 * r /G
This formula must work also for the jet stream due to the Virial theorem (based on the same radius).
So, do you agree that if a molecular gets to a distance of 20,000 Ly above the center, it should feel the impact of a total center mass of:
M total = 220 K/s ^2 * 10,000LY /G
In order for the molecular jet stream to fly direct upwards (without any orbital movement) it is clear that the upwards force must be significantly stronger than the impact of the gravity force (due to the M total mass by Virial theorem).
So, which kind of force can do it?
Our scientists say that it must be magnetism.
So, the total gravity force on a molecular at radius r is:
F = G M (total) m(molecular)/ r^2
After placing the value of M total in the formula:
F = G V^2 * r m /G r^2 = m V^2 /r
The gravity force on any molecular in that molecular jet stream and at any radius from the center should be:
F gravity = m (molecular) 220km/s ^2 /r
Hence, In order to set that kind of a direct flow of the molecular jet stream, F magnetism must be significantly higher than F gravity.
Any idea about how much stronger it should be?

Quote from: Kryptid on 19/08/2019 13:52:08
You can calculate the force that a magnetic field has on a charged particle using the following equation:
F = qvBsinθ, where
“F” is the resulting force in newtons
“q” is the charge in coulombs
“v” is the velocity in meters per second
“B” is the magnetic field strength in teslas (1 tesla = 10,000 gauss)
“sinθ” is the angle between the direction of the particle’s motion and the direction of the magnetic field lines
Thanks for this explanation.
Although, we might not need it. As the gravity force can give us fairly good indication for the requested magnetism force.
In any case, I still wonder why the molecular jet stream doesn't orbit around the center of the galaxy as any other star in the galaxy?
Could it be that they are not effected by the Virial theorem and dark matter?
If so, why is it?

« Last Edit: 19/08/2019 17:04:04 by Dave Lev »
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Offline Halc

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Re: How gravity works in spiral galaxy?
« Reply #522 on: 19/08/2019 18:37:06 »
Quote from: Dave Lev on 19/08/2019 14:38:57
That brings me to the following critical issue with regards to The Virial Theorem and Dark Matter:
Our scientists claim that our Sun orbits around the center of the galaxy due to the impact of The Virial Theorem and Dark Matter.
I don't think any scientist claims that.  Theorems don't have any impact for one thing.
Yes, the sun orbits the galaxy at a rate that is a function of the mass distribution, including dark matter, which I see you're accepting now instead of being in total denial in prior posts.

Quote
It is also stated:
https://web.stanford.edu/~ajlucas/The%20Virial%20Theorem%20and%20Dark%20Matter.pdf
"Modern estimates put the percentage of the universe made up of dark matter at about 80-90%."
The figure is more like 27%, but maybe it's not including all mass/energy.  The statement doesn't specify 80-90% of what, so it is kind of vague.

Quote
Based on the Virial Theorem, do you agree that same total mass that holds by gravity any star (including the Sun) in the spiral disc must also apply to that molecular Jet stream (for the same radius)?
The theorem is irrelevant to the question.  The theorem only applies to systems in thermal equilibrium, and thus not to a jet stream.
Secondly, no.  The total mass around which the sun orbits is orders of magnitude larger than the total mass acting on your jet of molecules.

Quote
The orbital velocity for any star in the spiral disc is:
V^2 = G M /r
That formula is for a spherical distribution of mass.  A disk is not a sphere.  The calculation is more complicated than this simple case.  Yes, you can compute Earth's orbital speed around the sun with that formula.

Quote
M total (due to viral + Dark matter) = V^2 r /G
Virial theorem is not a mass.  It can be used to compute limits on energy.  I think you mean
M total (Ordinary matter + Dark matter) = V^2 r /G, which is still wrong because the mass is not spherically distributed.

Quote
As most of the stars in the spiral disc orbits at 220 K/s
Than the total center mass that with regards to the radius is:
M total = 220 K/s ^2 * r /G
This formula must work also for the jet stream due to the Virial theorem (based on the same radius).
It does not work for the jet stream which is not in a stable orbit.

Quote
So, do you agree that if a molecular gets to a distance of 20,000 Ly above the center, it should feel the impact of a total center mass of:
M total = 220 K/s ^2 * 10,000LY /G
No.  It isn't orbiting, so the calculation is meaningless.

Quote
In order for the molecular jet stream to fly direct upwards (without any orbital movement) it is clear that the upwards force must be significantly stronger than the impact of the gravity force (due to the M total mass by Virial theorem).
You haven't invoked the virial theorem in any of this, other than to drop its name now and then.  You seem to have no idea what it means.

Quote
So, the total gravity force on a molecular at radius r is:
F = G M (total) m(molecular)/ r^2
'Molecular' is an adjective, not a noun. A molecular has no more mass than does 'daft'.  Perhaps you mean the force on a given molecule.

Quote
After placing the value of M total in the formula:
F = G V^2 * r m /G r^2 = m V^2 /r
The gravity force on any molecular in that molecular jet stream and at any radius from the center should be:
F gravity = m (molecular) 220km/s ^2 /r
The formula is I suppose meaningful, but your lack of ability in applied mathematics means you've no idea what you've computed.  Want a clue?

Quote
Hence, In order to set that kind of a direct flow of the molecular jet stream, F magnetism must be significantly higher than F gravity.
What you computed was obviously independent of gravity or the mass of the galaxy or a black hole, none of which appear in your equation.  So your 'Hence' is completely mistaken.
« Last Edit: 19/08/2019 23:57:25 by Halc »
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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #523 on: 19/08/2019 21:57:15 »
Quote from: Dave Lev on 19/08/2019 14:38:57
So, as we move closer to the center of the SMBH, the magnetic field is stronger.
Therefore, if new pair of particles had been created at the event of horizon or very close it:
https://en.wikipedia.org/wiki/Pair_production
"Pair production is the creation of a subatomic particle and its antiparticle from a neutral boson."
"if one particle has electric charge of +1 the other must have electric charge of −1, or if one particle has strangeness of +1 then another one must have strangeness of −1"
Do you agree that at the moment of creation, one particle has electric charge of +1 while the other must have electric charge of −1 and they are probably moving very close to each other at high orbital velocity.
Do you agree that Lorentz force due to that magnetic power of 10,000 Gauss could affect their movement directions?

This would only be true for black holes that are small enough to create positron-electron pairs or heavier particles. Super-massive black holes can only create neutral particle pairs such as photons or gravitons.

Quote from: Dave Lev on 19/08/2019 14:38:57
If one will be pushed inwards to the center of the SMBH, the other one will be pulled outwards from the event horizon (directly into the accretion disc) at the same moment of creation due to Lorentz force under opposite electric charges.
Why not?

Magnetic fields neither attract nor repel electric charges. All they do is deflect their path (assuming they weren't traveling exactly parallel to the field lines, that is). The result is that the charged particles spiral around the lines (either clockwise or counterclockwise, depending on their charge). So it isn't a matter of one kind of charge being attracted towards the source of the magnetic field while the other is repelled. So you wouldn't get any preferential treatment of one kind of charge moving away from the hole with the other moving towards it.

Quote from: Dave Lev on 19/08/2019 14:38:57
If you agree with that, than the accretion disc gets its matter from the event of horizon (or deeper) without any violation of any law of physics

Well, not from super-massive black holes. All they do is emit radio waves. They don't have the tidal forces needed to produce matter like electrons or protons.

Quote from: Dave Lev on 19/08/2019 14:38:57
Halc have asked the same question

So where is the answer? Where did you get the measurement of 0.8c for a jet from a super-massive black hole?

Quote from: Dave Lev on 19/08/2019 14:38:57
Based on the Virial Theorem, do you agree that same total mass that holds by gravity any star (including the Sun) in the spiral disc must also apply to that molecular Jet stream (for the same radius)?
If so, how could it be that in the spiral arms we see clearly that the all stars obey to that Virial Theorem and orbit around the center, while the molecular jet stream ignore it completely?

Astrophysical jets travel far, far above the escape velocity of galaxies. Most stars do not.

Quote from: Dave Lev on 19/08/2019 14:38:57
Hence, In order to set that kind of a direct flow of the molecular jet stream, F magnetism must be significantly higher than F gravity.
Any idea about how much stronger it should be?

For any particular particle being send out into the jets, I agree that the total force sending it away from the hole must be much stronger than any pulling it inward. I would like to do some calculations in order to find that, but I'm missing some information. For example, I don't know the particle's acceleration. We have measured the final velocity of the jets (close to light speed in some cases), but how long did it take to reach those speeds?

I did do a very rough calculation that suggested a proton could be accelerated to 80% the speed of light by a 10,000 gauss field in something like 0.02 seconds, but the problem with that math is that it assumes that the field strength is constant throughout those 0.02 seconds. Since the proton travels over 2,000 kilometers in that time frame, that is almost certainly not true. Magnetic fields quickly weaken the further you get from their source. I would probably need calculus to get a good answer, and I'm no good at using that form of math.

Quote from: Dave Lev on 19/08/2019 14:38:57
In any case, I still wonder why the molecular jet stream doesn't orbit around the center of the galaxy as any other star in the galaxy?
Could it be that they are not effected by the Virial theorem and dark matter?
If so, why is it?

Escape velocity.

I'm still waiting for you to address this:

Quote from: Kryptid on 18/08/2019 18:42:07
So that gives us two options. Either:

(1) You agree with the laws of physics and therefore agree that your own model (which posits a violation of the first law of thermodynamics) is wrong.
(2) You agree with your model and therefore do not agree with the first law of thermodynamics.

Which is it? You can't have it both ways.
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Offline evan_au

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Re: How gravity works in spiral galaxy?
« Reply #524 on: 20/08/2019 00:14:52 »
Quote from: DaveLev
Hence, In order to set that kind of a direct flow of the molecular jet stream, F magnetism must be significantly higher than F gravity.
Any idea about how much stronger it should be?
This information was provided in a (much) earlier reference.
- The jet can be ejected from the accretion disk at up to 2x escape velocity
- For locations near the event horizon, the escape velocity exceeds 0.5c, so relativistic speeds for the jet is understandable
- But this mechanism also applies to jets from stellar-mass black holes, neutron stars, protoplanetary disks and even brown dwarf stars. So it doesn't need Hawking radiation  or pair production from a micro black hole to produce a jet.

Quote
So, as we move closer to the center of the SMBH, the magnetic field is stronger.
A few corrections:
1. As you move closer to the event horizon of a black hole, the magnetic field is stronger. (Reason: nothing inside the event horizon will have an effect outside the event horizon)
2. As you move closer to the innermost edge of an accretion disk, the magnetic field is stronger. (Reason: the magnetic field originates in the accretion disk.)
3. The jet does not originate from the black hole, it originates from matter already in the accretion disk, fed from matter already outside the black hole.
3.1 The jet does not originate from within the photon sphere (1.5x event horizon radius), as only electromagnetism can easily escape from there
3.2 The jet probably does not originate from within the LSCO (3x event horizon radius), as matter has great difficulty escaping from there
3.3 We need to look at the MHD (Magneto-Hydro Dynamic) simulations to see exactly where the matter and magnetic fields come from - but it's not from within the event horizon.
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #525 on: 20/08/2019 19:20:10 »
Quote from: Halc on 19/08/2019 18:37:06
Quote
The orbital velocity for any star in the spiral disc is:
V^2 = G M /r
That formula is for a spherical distribution of mass.  A disk is not a sphere.  The calculation is more complicated than this simple case.  Yes, you can compute Earth's orbital speed around the sun with that formula.
Thanks
So, let's look on Newton Shell theorem
https://en.wikipedia.org/wiki/Shell_theorem
"the shell theorem gives gravitational simplifications that can be applied to objects inside or outside a spherically symmetrical body. This theorem has particular application to astronomy."
Outside a shell"
"A solid, spherically symmetric body can be modelled as an infinite number of concentric, infinitesimally thin spherical shells. If one of these shells can be treated as a point mass, then a system of shells (i.e. the sphere) can also be treated as a point mass"
So, this gives a clear indication how we should use that Newton Shell theorem.
Based on this explanation, there is no restriction for any orbital movement.
Therefore, if we could hold the Sun at it's current location - (without any orbital movement, it shouldn't change it's gravity force - as long as it there and there is no change in the radius.
Dark matter -
We have already discussed deeply the great impact of the dark matter.
It is clear to all of us the the density of the dark matter is increasing as we move in.
There is a spicial formula for the dark matter in the Milky way.
Our scientists claim that the real matter can't hold the Sun in its orbital path.
Therefore, the real matter is almost neglected with regards to the dark matter (which has the greatest impact on the Sun gravity force - based on our scientists).

Newton Shell theorem works the same for any direction.
Therefore, if the Sun is on the spiral disc or high above the accretion disc - The gravity force should be the same for the same radius.
So, if we will place the Sun directly above the accretion disc at 27,000 Ly it will face exactly the same gravity force as it gets while it is on the spiral disc at that radius.
In the same token, if the Sun is orbiting around the SMBH, falling in directly to the SMBH or ejected  directly outwards from the SMBH - the gravity force at 27,000 LY will be absolutely the same.
In the same token, there is no difference if at 27,000 Ly we place the Sun, the moon or just single water' molecular.
They all should feel the same impact from the same center of mass (As all the mass in the shell is concentrated at the center of the Shell.
 
Quote from: Halc on 19/08/2019 18:37:06
It does not work for the jet stream which is not in a stable orbit.
I don't understand on which law do you base this statement?
https://en.wikipedia.org/wiki/Shell_theorem#/media/File:Shell-diag-1-anim.gif
In this diagram we see clearly that m is located at a fixed distance/radius from the shell' center.
There is no requirement for any stable orbit in the Newton Shell Theorem.
So, would you kindly explain why do you add that unexppected request?
In
Quote from: Halc on 19/08/2019 18:37:06
No.  It isn't orbiting, so the calculation is meaningless
If there is no request for orbiting - then my calculations are correct.
Quote from: Kryptid on 19/08/2019 21:57:15
This would only be true for black holes that are small enough to create positron-electron pairs or heavier particles.
Thanks
Quote from: Kryptid on 19/08/2019 21:57:15
Super-massive black holes can only create neutral particle pairs such as photons or gravitons.
In one hand you claim that a SMBH is the same as BH.
On the other hand based on this answer, they are different.
Is it just the size that set this impact?
Why at different radius of the SMBH we can't get different kind of new partials?
Why are you so sure about the activities in the SMBH while our real data about it is so limited?
Do we really know if there are layers in the SMBH or not? If yes, how many? If no - Please prove it.
Quote from: Kryptid on 19/08/2019 21:57:15
Magnetic fields neither attract nor repel electric charges. All they do is deflect their path (assuming they weren't traveling exactly parallel to the field lines, that is).
So, the magnetic field deflects the new born particles path.
Each charge will be deflected to different direction.
That's all we need!
Hence, assuming that particles pair orbit the SMBH/BH at ultra high velocity on their first moment of birth, than if based on Lorentz force one charge will be deflected outwards, than the other one should be deflected inwards.
I don't understand why do you claim:
Quote from: Kryptid on 19/08/2019 21:57:15
So it isn't a matter of one kind of charge being attracted towards the source of the magnetic field while the other is repelled.
I don't care about the source of the magnetic field. As long as it can deflected the path - that is perfectly Ok with me.
Quote from: Kryptid on 19/08/2019 21:57:15
Astrophysical jets travel far, far above the escape velocity of galaxies. Most stars do not.
That is 100% correct.
The question is: What can we learn from that? Remember, Newton Shell theorem works on m if it is Hydrogen Atom or if it is the Sun.
We can't just claim that Newton Shell theorem is working according to our wishful list. It must work everywhere and anywhere exactly the same.
Therefore, we need to explain that verification based on real law.
Quote from: Kryptid on 19/08/2019 21:57:15
Escape velocity.
I'm still waiting for you to address this:
Once you agree that Atom and stars are working based on the same law and the same Newton Shell theorem, you would see how easy it is.
Quote from: evan_au on 20/08/2019 00:14:52
- The jet can be ejected from the accretion disk at up to 2x escape velocity
- For locations near the event horizon, the escape velocity exceeds 0.5c, so relativistic speeds for the jet is understandable
- But this mechanism also applies to jets from stellar-mass black holes, neutron stars, protoplanetary disks and even brown dwarf stars.
Do you really see in your vision that all those stars are working together just to eject this jet stream?
Don't you think that they also need to complete their orbital cycle?
So, at any given moment the forces from those stars are changing, while the jet stream is moving constantly in the amplitude and at the same direction.
Hence, do you still consider that those stars can set that kind of jet stream?
A few corrections:
Quote from: evan_au on 20/08/2019 00:14:52
1. As you move closer to the event horizon of a black hole, the magnetic field is stronger.
Agree

Quote from: evan_au on 20/08/2019 00:14:52
2. As you move closer to the innermost edge of an accretion disk, the magnetic field is stronger.
Agree
Quote from: evan_au on 20/08/2019 00:14:52
(Reason: the magnetic field originates in the accretion disk.)
I don't agree.
Quote from: evan_au on 20/08/2019 00:14:52
3. The jet does not originate from the black hole, it originates from matter already in the accretion disk,
Agree, but not directly.
Quote from: evan_au on 20/08/2019 00:14:52
fed from matter already outside the black hole.
disagree
Quote from: evan_au on 20/08/2019 00:14:52
3.1 The jet does not originate from within the photon sphere (1.5x event horizon radius), as only electromagnetism can easily escape from there
We have already agreed that the jet originates from matter already in the accretion disk.
However, from this zone, new particles escape directly to the accretion disc. Yes - electromagnetism is responsible for that activity.
Quote from: evan_au on 20/08/2019 00:14:52
3.3 We need to look at the MHD (Magneto-Hydro Dynamic) simulations to see exactly where the matter and magnetic fields come from - but it's not from within the event horizon.
I'm not sure about the simulation.
However, I'm quite sure that one day we will discover the real main source for that ultra requested magnetic field (and it isn't the accretion disc).
« Last Edit: 20/08/2019 19:41:22 by Dave Lev »
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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #526 on: 20/08/2019 20:30:56 »
No more running, Dave Lev. I'm going to keep posting this question until you answer it.

Quote from: Kryptid on 19/08/2019 21:57:15
So that gives us two options. Either:

(1) You agree with the laws of physics and therefore agree that your own model (which posits a violation of the first law of thermodynamics) is wrong.
(2) You agree with your model and therefore do not agree with the first law of thermodynamics.

Which is it? You can't have it both ways.
« Last Edit: 21/08/2019 21:14:51 by Kryptid »
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Offline Halc

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Re: How gravity works in spiral galaxy?
« Reply #527 on: 20/08/2019 21:01:52 »
Quote from: Dave Lev on 20/08/2019 19:20:10
Quote from: Halc
Quote
The orbital velocity for any star in the spiral disc is:
V^2 = G M /r
That formula is for a spherical distribution of mass.  A disk is not a sphere.  The calculation is more complicated than this simple case.  Yes, you can compute Earth's orbital speed around the sun with that formula.
So, let's look on Newton Shell theorem
https://en.wikipedia.org/wiki/Shell_theorem
"the shell theorem gives gravitational simplifications that can be applied to objects inside or outside a spherically symmetrical body. This theorem has particular application to astronomy."
"A solid, spherically symmetric body can be modelled as an infinite number of concentric, infinitesimally thin spherical shells. If one of these shells can be treated as a point mass, then a system of shells (i.e. the sphere) can also be treated as a point mass"
So, this gives a clear indication how we should use that Newton Shell theorem.
That clear indication is that you can't use it since matter both inside and outside the shell of the sun's orbit is not spherically arranged.  That's why I said your formula above doesn't work for a galaxy.
Again, your lack of reading comprehension skills is showing.  You quote the very parts that invalidate the use of the shell theorem in a model of a disk-arrangement of matter like a galaxy.

Quote
Dark matter -
We have already discussed deeply the great impact of the dark matter.
You denied its existence actually. So you both deny it and find it having a great impact.  You're at least consistent in your inconsistency.

Quote
Newton Shell theorem works the same for any direction.
Therefore, if the Sun is on the spiral disc or high above the accretion disc
The theorem doesn't apply to the motion of the sun, so there is no 'therefore' about it.
Quote
So, if we will place the Sun directly above the accretion disc at 27,000 Ly it will face exactly the same gravity force as it gets while it is on the spiral disc at that radius.
Exactly wrong.
Quote
Quote from: Halc
M total = 220 K/s ^2 * r /G
This formula
must work also for the jet stream due to the Virial theorem
It does not work for the jet stream which is not in a stable orbit.[/quote]
I don't understand on which law do you base this statement?[/quote]If you actually read about the virial theorem, it only concerns stable systems like regular orbits.  The jet is not such a thing, so the theorem (which you never invoked except by name) is inapplicable. The formula you quote does not come from the virial theorem. It is an invalid application of one of Newton's laws, essentially giving a spherically distributed mass necessary for our orbit.  Since the mass is not spherically distributed, it inaccurately computes the higher actual mass of all the material within our orbital radius.
Quote
There is no requirement for any stable orbit in the Newton Shell Theorem
So, would you kindly explain why do you add that unexppected request?.
Never said there was.  The shell theorem concerns spherical shells, not orbits.  The virial theorem on the other hand concerns stable systems.
Matter exiting a system at escape velocity is not a stable system.
Try actually reading about both and understanding them before using both incorrectly.
Quote
In
Quote from: Halc on 19/08/2019 18:37:06
No.  It isn't orbiting, so the calculation is meaningless
If there is no request for orbiting - then my calculations are correct.
The formula you quoted is only meaningful to a description of an orbit.
Quote
In one hand you claim that a SMBH is the same as BH.
On the other hand based on this answer, they are different.
Is it just the size that set this impact?
Yes.  Tidal forces near the event horizon are inversely proportional to the mass of the object.
Quote
Why at different radius of the SMBH we can't get different kind of new partials?
Tidal forces get even weaker with distance.
Quote
Do we really know if there are layers in the SMBH or not? If yes, how many? If no - Please prove it
Doesn't matter, per no-hair theorem.
Quote
We can't just claim that Newton Shell theorem is working according to our wishful list. It must work everywhere and anywhere exactly the same.
It must work only where there are shells.  A galaxy is lacking in them.
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #528 on: 21/08/2019 20:47:26 »
Quote from: Halc on 20/08/2019 21:01:52
The shell theorem concerns spherical shells, not orbits.  The Virial theorem on the other hand concerns stable systems.
Matter exiting a system at escape velocity is not a stable system.
Try actually reading about both and understanding them before using both incorrectly.
Ok
Let's verify the Virial Theorem
http://hosting.astro.cornell.edu/academics/courses/astro201/vt.htm
"We can estimate the Virial Mass of a system if we can observe:
The true overall extent of the system Rtot
The mean square of the velocities of the individual objects that comprise the system"
" in a spiral galaxy, the dominant motion of the stars in the disk is circular rotation in the plane of the disk. The variation in the orbital velocities with radius V(r) is called the rotation curve."
With regards to spiral galaxy-
We have good verification about all stars in the spiral disc including their mass and orbital velocities.
However:
1. Dark matter
It is stated clearly - "We can estimate the Virial Mass of a system if we can observe"
Do we observe the dark matter?
What do we really know about the dark matter? How does it work in the galaxy?
Does it stay in some sort of cloud? Is it moving as a wind in a turbulent or is it orbit around something?
Could it be that it orbits around the real matter and not around the galaxy center and at what velocity?
Do we know for sure that the dark matter meets the following two main requirements for using the Virial theorem:
A. The true overall extent of the system Rtot - for Dark matter?
B. The mean square of the velocities of the individual dark matter objects that comprise the system?
How can we still use the Virial Theorem if we can't observe the the dark matter and if we have no idea how and if it orbits?
Could it be that our scientists are using a none relevant theorem for something that they don't know how it works?

2. Stable system:
Quote from: Halc on 20/08/2019 21:01:52
The Virial theorem on the other hand concerns stable systems.
Matter exiting a system at escape velocity is not a stable system.

Do you really believe that the Milky way is a stable system?
https://curiosity.com/topics/this-hypervelocity-star-was-ejected-from-the-milky-way-curiosity
This Hypervelocity Star Was Ejected from the Milky Way.
Hypervelocity stars are rather rare in our galaxy. The first one was discovered in 2005, and so far researchers have discovered fewer than 30 of them. They travel at more than 1 million miles per hour, or 500 kilometers per second, twice as fast as other stars, and it takes an enormous amount of energy to propel them to that velocity."
We have found 30 Hypervelocity stars that had been ejected from the galaxy.
How the galaxy can be considered as "stable system" while we clearly see that at least 30 Hypervelocity stars had been ejected from it.
It is also stated:
"it takes an enormous amount of energy to propel them to that velocity."
As the Virial theorem is all about energy, how that "enormous amount of energy" could impact our calculation?
Yes, we only see 30 Stars, but it gives an indication for none stable system
« Last Edit: 21/08/2019 20:51:30 by Dave Lev »
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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #529 on: 21/08/2019 21:15:29 »
Why are you afraid of this question?

Quote from: Kryptid on 19/08/2019 21:57:15
So that gives us two options. Either:

(1) You agree with the laws of physics and therefore agree that your own model (which posits a violation of the first law of thermodynamics) is wrong.
(2) You agree with your model and therefore do not agree with the first law of thermodynamics.

Which is it? You can't have it both ways.
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #530 on: 22/08/2019 12:39:45 »
Quote from: Kryptid on 21/08/2019 21:15:29
So that gives us two options. Either:

(1) You agree with the laws of physics and therefore agree that your own model (which posits a violation of the first law of thermodynamics) is wrong.
(2) You agree with your model and therefore do not agree with the first law of thermodynamics.
There is no contradiction between my model to the First law of thermodynamics.
I have already explained it.
However, I'm not going to ask you to look for that answer as I will do it one more time for you and with pleasure.

1. New created particles - New pair of particles are created constantly around the SMBH (at the event of horizon or below). If one particle carry a positive charge, the other one gets a negative charge.
2. Magnetics field - Around the SMBH there is magnetic field. This magnetic field is quite strong at the event of horizon (or deeper?...)
Quote from: evan_au on 20/08/2019 00:14:52
As you move closer to the event horizon of a black hole, the magnetic field is stronger.
3. Lorentz force - Based on Lorentz force, the magnetic fields deflects differently the path of the orbital new born particles pair:
Quote from: Kryptid on 19/08/2019 21:57:15
Magnetic fields neither attract nor repel electric charges. All they do is deflect their path (assuming they weren't traveling exactly parallel to the field lines, that is).
Hence, if the positive charged particle will be deflected outwards, the negative charged particle will be deflected inwards.
Therefore, while the negative is pushed inwards into the center of the SMBH, the positive is pulled outwards and get's eventually into the accretion disc.

Would you kindly explain where is the contradiction?

« Last Edit: 22/08/2019 12:41:47 by Dave Lev »
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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #531 on: 22/08/2019 16:00:19 »
Quote from: Dave Lev on 22/08/2019 12:39:45
1. New created particles - New pair of particles are created constantly around the SMBH (at the event of horizon or below).

Right.

Quote
If one particle carry a positive charge, the other one gets a negative charge.

For very small black holes, this would be true. This would not be true for super-massive black holes as they have insufficient tidal forces to produce anything other than photons, gravitons and maybe neutrinos. Charged particles like electrons, protons or muons have too much mass-energy to be generated by the (relatively) weak tidal forces present.

Quote from: Dave Lev on 22/08/2019 12:39:45
2. Magnetics field - Around the SMBH there is magnetic field. This magnetic field is quite strong at the event of horizon (or deeper?...)

Although true black holes cannot have such a magnetic field, I will submit to the possibility that something like MECOs (magnetospheric eternally collapsing objects) could, maybe, be what "black holes" actually are. So I will tentatively agree that "black holes" could be MECOs and as such could have magnetic fields. I'll consider this plausible for the sake of discussion: https://en.wikipedia.org/wiki/Magnetospheric_eternally_collapsing_object

Quote from: Dave Lev on 22/08/2019 12:39:45
3. Lorentz force - Based on Lorentz force, the magnetic fields deflects differently the path of the orbital new born particles pair:

Hence, if the positive charged particle will be deflected outwards, the negative charged particle will be deflected inwards.
Therefore, while the negative is pushed inwards into the center of the SMBH, the positive is pulled outwards and get's eventually into the accretion disc.

The Lorentz force would be there, but it wouldn't be "positive goes out and negative goes in". The Lorentz force would deflect the path of particles at a right angle to the field lines (assuming that they were already on a path perpendicular to the field lines. If they are parallel to the field lines, there is no force).

Quote from: Dave Lev on 22/08/2019 12:39:45
Would you kindly explain where is the contradiction?

The contradiction is your claim that this process causes the black hole to grow in mass. The mass of the black hole has to shrink, not grow, as the negative mass (not negative charge, an important difference) particle is invariably the one that passes into the hole (because the swapping of time and space coordinates inside of the event horizon is what makes that particular particle have a negative mass in the first place). That negative mass subtracts from the positive overall mass of the hole, causing it to become smaller. If you are willing to accept this point, then I will agree that your model no longer violates the first law of thermodynamics.
« Last Edit: 22/08/2019 16:06:34 by Kryptid »
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #532 on: 22/08/2019 20:13:31 »
Quote from: Kryptid on 22/08/2019 16:00:19
The contradiction is your claim that this process causes the black hole to grow in mass. The mass of the black hole has to shrink, not grow, as the negative mass (not negative charge, an important difference) particle is invariably the one that passes into the hole (because the swapping of time and space coordinates inside of the event horizon is what makes that particular particle have a negative mass in the first place). That negative mass subtracts from the positive overall mass of the hole, causing it to become smaller. If you are willing to accept this point, then I will agree that your model no longer violates the first law of thermodynamics.

Thanks Kryptid for this great answer.
So, you agree that new particles could be ejected outwards from the SMBH without any violation of first law of thermodynamics. However, you need my confirmation for your point of view:
Quote from: Kryptid on 22/08/2019 16:00:19
If you are willing to accept this point, then I will agree that your model no longer violates the first law of thermodynamics.
So, YES!!! I fully agree with your point!
If the matter in the SMBH is "positive overall mass", than "That negative mass subtracts from the positive overall mass of the hole, causing it to become smaller.
That is 100% correct.
However, I claim that the matter in the SMBH isn't "Positive overall mass" but "Negative overall mass".
Therefore, a new falling in negative particle should increase the total  "Negative overall mass".
As I have stated before, the SMBH acts as a "Negative overall mass barrel" that collects all new born negative particles.
So, we get into the accretion Disc the "Positive overall mass" while the SMBH gets all the "negative overall mass".
This activity is a Win-Win situation for our accretion disc and for the SMBH.
Both are increasing their mass constantly from this new particle pair creation.

Therefore, our SMBH isn't so bad eater. It actually has great appetite.
For any positive particle that it offers the accretion disc, it eats one negative particle.
Hence, it doesn't need to eat any particle from the accretion disc.
This is the solution for the following enigmas -
1. Why more than 99% of the matter in the accertion disc is ejected outwards?
2. Why we couldn't see any in falling matter - not from the accretion disc into the SMBH and not from outside into the accretion disc?


« Last Edit: 22/08/2019 20:46:10 by Dave Lev »
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Re: How gravity works in spiral galaxy?
« Reply #533 on: 23/08/2019 07:21:44 »
Quote from: Dave Lev on 22/08/2019 20:13:31
However, I claim that the matter in the SMBH isn't "Positive overall mass" but "Negative overall mass".

So you've gone from violating the first law of thermodynamics to violating the law of gravity.

If a black hole had negative mass, it wouldn't be a black hole because it would repel light and matter, not attract it (just as Halc said). Nothing could ever be in orbit around a black hole because it wouldn't be attracting anything. There would be no accretion disk, no orbiting stars, nothing of the sort.
« Last Edit: 23/08/2019 07:24:04 by Kryptid »
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #534 on: 23/08/2019 14:21:47 »
Quote from: Halc on 22/08/2019 22:04:11
Then a black hole would repel everything, since it would exert a negative gravitational force.
F=GMm/r².  So S2 would not orbit Sgr-A if the latter had negative mass.
No real object has negative mass.  The concept is strictly a mathematical one concerning non-real virtual particles, as discussed in prior posts.
On what kind of "evidence" do you base this understanding?
I do recall that you have stated that matter and Antimatter has the same gravity impact.
We can also see a confirmation for that in the following article:
https://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter
"The gravitational interaction of antimatter with matter or antimatter has not been conclusively observed by physicists. While the consensus among physicists is that gravity will attract both matter and antimatter at the same rate that matter attracts matter, there is a strong desire to confirm this experimentally."
If you still not sure about it, I would like to offer the following article from:
Sabine Hossenfelder - Sabine is a theoretical physicist specialized in quantum gravity and high energy physics. She also freelance writes about science.
https://www.forbes.com/sites/startswithabang/2017/03/29/why-doesnt-antimatter-anti-gravitate/#67be1a5419e2
"The standard model also includes all anti-particles, which are identical to their partner-particles except for having opposite electric charge. Is it possible that the anti-particles also anti-gravitate?
Theory clearly answer this question with a resounding, “No.” From the standard model, we can derive how antimatter gravitates – it gravitates exactly the same way as normal matter."
"Those with little faith in theoretical arguments might want to argue that maybe it’s possible to find a way to make antimatter anti-gravitate only sometimes. I am not aware of any theorem which strictly proves this to be impossible, but neither is there – to my best knowledge – any example of a consistent theory in which this has been shown to work."
"And if that still wasn’t enough to convince you, the ALPHA experiment at CERN has not only created neutral anti-hydrogen, made of an anti-proton and a positron (an anti-electron), but has taken great strides towards measuring exactly how anti-hydrogen behaves in Earth’s gravitation field. Guess what? So far there is no evidence that anti-hydrogen falls upwards – though the present measurement precision only rules out that the anti-hydrogen’s gravitational mass is not larger than (minus!) 65 times its inertial mass."
"Both matter and antimatter particles hold together the quarks that make up neutrons and protons. Indeed, the anti-particles’ energy makes a pretty large contribution to the total mass of neutrons and protons, and hence to the total mass of everything around us. This means if antimatter had a negative gravitational mass, the equivalence principle would be badly violated. It isn’t, and so we already know antimatter doesn’t anti-gravitate."

However, if you still have little faith in theoretical arguments and you disagree with Sabine Hossenfelder, than you are more than welcome to offer any article which supports your point of view.
« Last Edit: 23/08/2019 14:42:12 by Dave Lev »
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #535 on: 23/08/2019 16:39:27 »
Quote from: Halc on 23/08/2019 14:54:55
You suggested a negative mass object, not antimatter.
A negative mass black hole would very very much be distinct from a positive mass one due to the entirely empirical effect as described above.  The object would repel the entire galaxy and effectively squirt out one side somewhere.
Yes, I agree.
However, this was not my intention.
Sorry for that.
In the article it was stated:
Quote from: Dave Lev on 23/08/2019 14:21:47
"The standard model also includes all anti-particles, which are identical to their partner-particles except for having opposite electric charge. Is it possible that the anti-particles also anti-gravitate?
Theory clearly answer this question with a resounding, “No.” From the standard model, we can derive how antimatter gravitates – it gravitates exactly the same way as normal matter."

In this discussion we have focused on a pair of particles
One is partner-particle and the other one is anti particle.
They are fully identical except for having opposite electric charge.
As Kryptid had used the "Positive overall mass" for the positive electrical charged particles, I have used the "Negative overall mass" for the Negative electric charged particles.
So, it is not about negative or positive mass, it is all about positive or negative electric charged particles.
Therefore, as the positive electric charged particle represents the partner-particle, the Negative electric charged particle represents the Anti -Particle.
In any case, as you agree that:
Quote from: Halc on 23/08/2019 14:54:55
Antimatter still has positive mass.
An antimatter black hole is not distinct from a regular matter black hole, per no-hair theorem.
It is clear by now that antimatter or antiparticle has a positive mass
Therefore antimatter or antiparticle must have the same gravitational force as matter or positive particle.


« Last Edit: 23/08/2019 16:43:43 by Dave Lev »
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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #536 on: 23/08/2019 17:31:05 »
Quote from: Dave Lev on 23/08/2019 16:39:27
As Kryptid had used the "Positive overall mass" for the positive electrical charged particles

At no point did I equate positive mass with positive charge. They are distinct concepts. If the electron is the particle that escapes, then that would be a case of a negatively-charged particle with positive mass. Alternatively, if the positron is what falls in, then that is a positively-charged particle with negative mass. For a neutral black hole, the probability for an electron escaping is equal to the probability of a positron escaping because there is no preferential mechanism at work (and no, magnetic fields won't change this).

Quote from: Dave Lev on 23/08/2019 16:39:27
So, it is not about negative or positive mass, it is all about positive or negative electric charged particles.

It absolutely is about negative and positive mass, since we are talking about super-massive black holes (which cannot produce charged particles because those particles are too massive).

Quote from: Dave Lev on 23/08/2019 16:39:27
Therefore, as the positive electric charged particle represents the partner-particle, the Negative electric charged particle represents the Anti -Particle.

Positrons are antimatter. They are positively-charged.

To sum things up, your idea doesn't work because:

(1) Super-massive black holes have positive mass. We know this because things orbit them, and
(2) Super-massive black holes cannot produce electrically-charged particles.

Quote from: Halc on 23/08/2019 13:42:07
It would still be a black hole of sorts because it would attract itself. It wouldn't self-explode or anything.

Negative mass actually repels other negative mass. When you plug in the numbers for a pair of negative mass objects, you would initially expect the two to attract each other because two negative numbers multiplied by each other are positive. However, a negative inertial mass in addition to a negative gravitational mass means that it responds in the opposite way to a force acting on it. So an attraction is experienced as a repulsion: https://en.wikipedia.org/wiki/Negative_mass#Runaway_motion
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Offline Halc

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Re: How gravity works in spiral galaxy?
« Reply #537 on: 23/08/2019 19:13:54 »
Quote from: Kryptid on 23/08/2019 17:31:05
Negative mass actually repels other negative mass. When you plug in the numbers for a pair of negative mass objects, you would initially expect the two to attract each other because two negative numbers multiplied by each other are positive. However, a negative inertial mass in addition to a negative gravitational mass means that it responds in the opposite way to a force acting on it. So an attraction is experienced as a repulsion: https://en.wikipedia.org/wiki/Negative_mass#Runaway_motion
I had actually worked that out myself, but hadn't posted any of it yet.  There is a positive attraction between pairs of negative-mass objects, but that positive force results in negative acceleration due to F=ma, hence they act as if repelled.  Hence I figured out the funny positive and negative planets chasing each other, a sort of reactionless force.  It doesn't violate conservation of energy or Newton's 3rd law of motion since combined kinetic energy and momentum remain zero.  I was trying to drive it to inconsistency and have yet to actually do it.
I didn't know wiki had a site on the physics of macro negative mass.
The site calls the runaway motion 'preposterous', but what's actually wrong with it?

My idea of the black hole squirting out of the galaxy seems incorrect.
« Last Edit: 23/08/2019 19:18:28 by Halc »
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Offline Dave Lev (OP)

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Re: How gravity works in spiral galaxy?
« Reply #538 on: 23/08/2019 20:15:00 »
Quote from: Kryptid on 23/08/2019 17:31:05
To sum things up, your idea doesn't work because:
(1) Super-massive black holes have positive mass. We know this because things orbit them, and
(2) Super-massive black holes cannot produce electrically-charged particles.
I disagree with both statement:
"(1) Super-massive black holes have positive mass. We know this because things orbit them"
There is no such thing as "Negative mass". This is a fiction. We only discuss on matter/Antimatter, or Positive/Negative electric charged particles.
So, by now it is clear that the gravity force for matter/particle is identical to antimatter/antiparticle
"(2) Super-massive black holes cannot produce electrically-charged particles"
I disagree with that statement, mainly because our knowledge about BH and SMBH is very poor.
You give that kind of statement which is full with confidence, while we have no real verification. We don't know how the BH/SMBH really works and from what kind of matter/antimatter they have made of.
We don't know if they have a core and how many layers covers this core.
You even don't believe that the SMBH can generate magnetic fields.
Therefore, as long as our knowledge about the BH/SMBH is so poor, it's better to avoid from that kind of statement.
In any case, based on your theory a BH can produce electrically-charged particles.
So what is the difference between the BH to the SMBH?
The main difference is Mass.
That mass affects the gravity force.
So, do we know the requested gravity force that is needed to produce those electrically-charged particles in a BH?
Let's assume that we can sent a probe into the BH and monitor exactly the radius that is needed for the production of those electrically-charged particles.
Based on that radius, we can extract the gravity force.
However, we can get the same gravity force also at the SMBH.
We only need to get to the relevant radius.
For example -
F=GMm/r²
Let's assume that:
If BH mass = M
SMBH mass = M * 10^6
Therefore
If
r1 -  represents the requested radius in a BH for the production of electrically-charged particles.
Than:
F (BH)=GMm/r1²
r2 represents the requested radius in the SMBH which has the same gravity force as r1 in a BH
so the gravity force for the SMBH is:
F (SMBH) = GM* 10^6 m/r2²
F (BH)= F (SMBH)
GMm/r1² = GM* 10^6 m/r2² 
1/r1² = 10^6 /r2²
r2² = 10^6 * r1²
r2 = 10^3 * r1
So, if the mass of the SMBH is higher by 10^6 than the mass of a BH, at a radius which is bigger by 10^3 from the radius of the BH we will get the same gravity force.
That shows that the total mass of the SMBH is not relevant for production of electrically-charged particles.
It's all about gravity force which is a direct outcome of the radius.
If the BH can create electrically-charged particles at radius r1 the SMBH can do the same at radius r2.

In any case:
I have proved that whole your idea about the Virial theorem is totally wrong.
In that theory we must OBSERVED the orbital objects. As we can't observe the dark matter we can't know its orbital velocity (and if it has any sort of velocity)
Therefore our understanding of how the galaxy works must also be updated.
As we have based the gravity force that holds the Sun around the galaxy on the Virial theorem - than we must look for better theory.
How are you going to address this key issue?

« Last Edit: 23/08/2019 20:27:53 by Dave Lev »
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Offline Kryptid

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Re: How gravity works in spiral galaxy?
« Reply #539 on: 23/08/2019 21:35:17 »
Quote from: Dave Lev on 23/08/2019 20:15:00
I disagree with both statement:
"(1) Super-massive black holes have positive mass. We know this because things orbit them"
There is no such thing as "Negative mass". This is a fiction. We only discuss on matter/Antimatter, or Positive/Negative electric charged particles.
So, by now it is clear that the gravity force for matter/particle is identical to antimatter/antiparticle

You're contradicting yourself. If I say that black holes have positive mass and you also say that black holes have positive mass, then we are agreeing, not disagreeing. If you do believe that black holes have positive mass, then why did you make this statement earlier?

Quote from: Dave Lev on 22/08/2019 20:13:31
However, I claim that the matter in the SMBH isn't "Positive overall mass" but "Negative overall mass".

You can't say in one post that black holes have negative mass and in another post that they have positive mass. Make up your mind.

Quote from: Dave Lev on 23/08/2019 20:15:00
I disagree with that statement, mainly because our knowledge about BH and SMBH is very poor.

We wouldn't need to know anything about black holes at all in order to know that some certain minimum tidal force is necessary to separate a particle pair of a given energy. It's the basic laws of physics at work. Conservation of energy will not allow particle pairs to pop into existence without being given sufficient energy. Electrons and positrons, unlike photons, have a finite rest mass. This means you cannot have an electron or positron with arbitrarily low energy. Even in the rest frame of those particles, that minimum energy is 0.511 MeV per particle (or slightly less if they are bound in the form of a positronium atom). If the tidal forces cannot supply that needed level of energy, then you don't get particles. If you claim otherwise, then you are arguing for a violation of the first law of thermodynamics.

Quote from: Dave Lev on 23/08/2019 20:15:00
We don't know how the BH/SMBH really works and from what kind of matter/antimatter they have made of.

Irrelevant. Objects inside of the event horizon cannot have any effect on those outside the horizon (except from gravity). This is a widely-known and well-understood property of black holes. If information could get out, then it wouldn't be an event horizon.

Quote from: Dave Lev on 23/08/2019 20:15:00
We don't know if they have a core and how many layers covers this core.

Again, irrelevant as per my prior statement.

Quote from: Dave Lev on 23/08/2019 20:15:00
You even don't believe that the SMBH can generate magnetic fields.
Therefore, as long as our knowledge about the BH/SMBH is so poor, it's better to avoid from that kind of statement.

"Belief" is irrelevant. It is absolutely true that a neutral, classical black hole with a singularity and an event horizon cannot have an intrinsic magnetic field. This is why the no hair theorem is called a theorem. A theorem cannot be proven wrong because it has already been proven true: https://en.wikipedia.org/wiki/Theorem

The only way around that would be if black holes have a different structure than predicted. I will concede that this is possible, and have offered the MECO as an alternative example which could have an intrinsic magnetic field.

Quote from: Dave Lev on 23/08/2019 20:15:00
In any case, based on your theory a BH can produce electrically-charged particles.

Don't call it "my" theory. It isn't. It is the currently-accepted theory. The law of conservation of energy will only allow charged particles to be produced when the tidal forces are strong enough. Mathematical analysis by physicists have already been done that exclude super-massive black holes from producing charged particles. The needed tidal force is not present.

Quote from: Dave Lev on 23/08/2019 20:15:00
So what is the difference between the BH to the SMBH?
The main difference is Mass.
That mass affects the gravity force.

This is like asking what the difference is between a cat and a mammal. A cat is a type of mammal. Perhaps what you meant to ask is "what is the difference between a stellar-mass black hole and a super-massive black hole?" That question would make more syntactic sense.

Quote from: Dave Lev on 23/08/2019 20:15:00
So, do we know the requested gravity force that is needed to produce those electrically-charged particles in a BH?

Yes. I don't know what it is off the top of my head, but the calculations have already been done by physicists (Don N. Page, for example). I do know that, according to those calculations, a black hole with a mass much larger than 1014 kilograms (about one-tenth the mass of Mar's satellite Deimos) doesn't produce electron-positron pairs. Super-massive black holes are many, many orders of magnitude more massive than that. So you don't get charged particles from them. Such calculations are based purely on the known laws of physics and conservation of energy.

Come to think of it, since Hawking radiation resembles black-body radiation, I might actually be able to calculate the required minimum mass of a black hole where the majority of photons produced are at the needed energy level to form positron-electron pairs. I'll get on that.

Quote from: Dave Lev on 23/08/2019 20:15:00
The main difference is Mass.
That mass affects the gravity force.
So, do we know the requested gravity force that is needed to produce those electrically-charged particles in a BH?
Let's assume that we can sent a probe into the BH and monitor exactly the radius that is needed for the production of those electrically-charged particles.
Based on that radius, we can extract the gravity force.
However, we can get the same gravity force also at the SMBH.
We only need to get to the relevant radius.
For example -
F=GMm/r²
Let's assume that:
If BH mass = M
SMBH mass = M * 10^6
Therefore
If
r1 -  represents the requested radius in a BH for the production of electrically-charged particles.
Than:
F (BH)=GMm/r1²
r2 represents the requested radius in the SMBH which has the same gravity force as r1 in a BH
so the gravity force for the SMBH is:
F (SMBH) = GM* 10^6 m/r2²
F (BH)= F (SMBH)
GMm/r1² = GM* 10^6 m/r2² 
1/r1² = 10^6 /r2²
r2² = 10^6 * r1²
r2 = 10^3 * r1
So, if the mass of the SMBH is higher by 10^6 than the mass of a BH, at a radius which is bigger by 10^3 from the radius of the BH we will get the same gravity force.
That shows that the total mass of the SMBH is not relevant for production of electrically-charged particles.
It's all about gravity force which is a direct outcome of the radius.
If the BH can create electrically-charged particles at radius r1 the SMBH can do the same at radius r2.

The fatal flaw in your calculations is that you are considering the overall gravitational force, not the tidal force. Redo the calculations, but for tidal forces, and you'll be on the right track.

Quote from: Dave Lev on 23/08/2019 20:15:00
In any case:
I have proved that whole your idea about the Virial theorem is totally wrong.

Since when have I ever said anything about virial theorem, let alone say that it was "my idea"? Or are you talking to Halc here?

Quote from: Dave Lev on 23/08/2019 20:15:00
In that theory we must OBSERVED the orbital objects. As we can't observe the dark matter we can't know its orbital velocity (and if it has any sort of velocity)
Therefore our understanding of how the galaxy works must also be updated.
As we have based the gravity force that holds the Sun around the galaxy on the Virial theorem - than we must look for better theory.
How are you going to address this key issue?

What does any of that have to do with the behavior of super-massive black holes?
« Last Edit: 23/08/2019 22:05:57 by Kryptid »
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